Abstract: A data sending system which prevents a parity error occurrence in a data receiving unit is provided. The data sending system provided is related to data sending systems and, particularly, to a data sending system where plurality of data sending units share a path for data transmission. The data sending system provided comprises a network consisting of a data path and control path, a control unit for instructing data sending through said control path, one or plural data sending units for sending, according to an instruction from said control path, data to a specific one of plural logical paths of said data path, and a data receiving unit permanently connected to the one of plural logical paths of said data path. Said control unit has a determining section which determines a time span, during which no sending data exists in a logical path connected to said data receiving unit, and also instructs a specific unit of said data sending units to send dummy data during the time span.

Abstract: A video conferencing system uses video conferencing terminals at a number of locations to allow each of participants in a video conference to watch other participants he or she wants to watch in a desired array using a small amount of hardware. The system comprises first image reduction and storage units for reducing images from the terminals at a reduction ratio for speaker's image and storing the reduced images, second image reduction and storage units for reducing the images from the terminals at a reduction ratio for non-speaker's image and storing the reduced images, image readout control units for reading the reduced image stored in a corresponding one of the second image reduction and storage units in such a way that a plurality of reduced images identical to that reduced image can be displayed on one display screen, and an image selecting and combining unit for generating a composite image and outputting it to receiving terminals.

Abstract: A camera controlling apparatus for a television conference system wherein the turning speed of a camera is varied in response to an operation mode. The camera controlling apparatus includes a preset control section for outputting a preset control signal for moving the camera at a first turning speed to a predetermined point, and a self room manual control section for outputting a self room manual control signal for moving the camera at a second turning speed lower than the first turning speed. The camera controlling apparatus further includes a reception manual control section for outputting a reception manual control signal for moving the camera at a third turning speed lower than the second turning speed in response to a manual signal transmitted thereto by way of a communication line. Any of the control signals is inputted to a speed control section, and the camera is controlled to be turned at a turning speed represented by the thus inputted control signal by the speed control section.

Abstract: A television conference system having at least one of the functions of automatically directing a camera toward a speaker, of transmitting video signals of picture images from a plurality of television cameras, and of displaying a document image.

Abstract: A multi-point conference system for making a video conference includes a center unit having a controller and an image selector, and three or more stations respectively coupled to the center unit, where each station includes at least one camera for picking up an image to output an image data, a display for displaying an image based on an image data and a request part for making a request. The controller initially sets master, sub and participating stations in conformance with a predetermined rule. The image selector automatically supplies the image data from the master station to the sub and participating stations to be displayed on the display thereof and supplies the image data from the sub station to the master station to be displayed on the display thereof.